The present invention relates to control systems and particularly to systems for controlling fluid flow. More particularly, the present invention relates to electronic control systems for regulating flow of air and fuel for industrial burners.
Industrial burners typically operate under varying conditions such as variable fuel and air supply pressures and temperatures, back pressure from the burner, humidity, fuel quality, etc. In comparison to a burner control system that is calibrated for a particular set of operating conditions, a control system that automatically compensates for changes in the burner operating environment will optimize burner performance over the changing conditions. A burner control system that provides improved precision in regulating the flow of air and fuel will allow for operation over a wider burner turndown and increase overall burner efficiency, resulting in reduced emissions over the entire operating range, as well as increasing reliability and burner operating life.
In accordance with the present invention, an intelligent burner control apparatus is provided for controlling the rate of a fluid flow in a burner system from a fluid supply to a burner. The burner system includes an electronic communication network. The apparatus includes a flow controller including a sensor and a communication module. The sensor is configured to be coupled between the fluid supply and the burner to measure the fluid flow rate. The communication module is configured to be coupled to the communication network to send on the measured fluid flow rate. The apparatus also includes a flow regulator including a communication module and an actuator. The communication module of the flow regulator is configured to be coupled to the communication network to receive the flow control signal. The actuator is configured to be coupled between the fluid supply and the burner to control the fluid flow rate. The flow regulator is configured to command the actuator based on the flow control signal.
In preferred embodiments, the sensor is a mass flow sensor, such as a thermal mass flow sensor. The actuator can include a variable speed blower, or a valve actuator coupled to a valve assembly, or both a variable speed blower and a valve actuator coupled to a valve assembly. The communication network can be a peer-to-peer communication network.
The intelligent burner control apparatus further includes a brain module configured to be coupled to the communication network and to send a flow set point signal indicative of a desired fluid flow rate over the communication network. The flow controller module is configured to receive the flow set point signal and determine the flow control signal based on the measured flow rate and flow set point signal. The brain module can be configured to receive a firing rate signal and to determine the flow set point based on the firing rate signal. The brain module can monitor the rate of change in the firing rate signal from a process controller, and if the rate of change exceeds a predetermined threshold then the burner brain determines and sends a plurality of intermediate setpoints over the communication network.
The intelligent burner control apparatus further includes a display module configured to be coupled to the communication network. The display module includes a display terminal and is configured to receive at least one display signal over the communication network. The display module provides an indication on the display terminal indicative of the display signal. The intelligent burner control apparatus can include a command module configured to be coupled to the communication network. The command module includes a user input device for sending at least one user command over the communication network.
Additional features of the invention will become apparent to those skilled in the art upon consideration of the following detailed description of preferred embodiments exemplifying the best mode of carrying out the invention as presently perceived.